Custom Params cannot be used in on-cel expressions with errors that appear to be bugs

Given a Repository CR with a custom param like below:

spec:
  params:
  - name: test_params
    value: "true"

The following on-cel-expressions do not work:

Using event_type == "push" && {{test_params == true}} results in the following error:

CEL expression evaluation error: expression "event_type == \"push\" && true == true" check failed: ERROR: <input>:1:1: undeclared reference to 'event_type' (in container '')  | event_type == "push" && true == true  | ^

Removing the curly braces from the custom-param results in a different error:

CEL expression evaluation error: expression "event_type == \"push\" && test_params == true" check failed: ERROR: <input>:1:1: undeclared reference to 'event_type' (in container '')  | event_type == "push" && test_params == true  | ^ ERROR: <input>:1:25: undeclared reference to 'test_params' (in container '')  | event_type == "push" && test_params == true  | ........................^

However if I remove the reference to event_type, using just the on-cel expression {{test_params == true}} then the pipelinerun is matched as expected...

Workaround

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